In order to enable Bi-Polar high frequency and Mono-Polar high frequency to be used at the same time, the large output power on a Mono-Polar basis has been fine-tuned so that it can be applied to Bi-Polar one as well. In case of Bi-Polar high frequency, the electro-repulsion function between poles has been strengthened and changed from the fast Bi-Polar way to Multi- Polar way, making Quad-Polar one possible. In this way, the treatment time has been reduced and more intensive treatment has become possible.